Computational Analysis of Cryogenic Stirling Refrigerator

Abstract

Abstract In the present work, a system consisting of two combined cryocoolers is simulated with the use of Computational Fluid Dynamics (CFD) and ANSYS Fluent software. The cryocoolers operate with frequency of 1 Hz and at temperature below 1 K. Instead of a matrix containing a regenerator, each of the machines employs a recuperator. The two recuperators exchange heat with each other, combining thus the two machines into one system. The working gas of the cryocoolers is helium-3 (He-3), the properties of which are obtained by the available literature for cryogenic temperatures. The setup of the presented simulation is based on a one-dimensional (1D) analytical model. The model is used to describe conducted experiments, in which ideal He-3 is the working gas of a similar system of Stirling cryocoolers and superfluid helium-4 (He-4) can pass through the pistons (super leak). The simulations results, including the fluctuation of gas temperature in the machine’s spaces, pressure drop, work and heat exchanged are presented.